The EPIC-Norfolk Study
Uncorrected refractive error in older British adults: the EPIC-Norfolk Eye Study.
The British journal of ophthalmology 2012 ; 96: 991-6.
Sherwin JC, Khawaja AP, Broadway D, Luben R, Hayat S, Dalzell N, Wareham NJ, Khaw KT, and Foster PJ
DOI : 10.1136/bjophthalmol-2011-301430
PubMed ID : 22535330
PMCID : PMC4624257
Abstract
To investigate the prevalence of, and demographic associations with, uncorrected refractive error (URE) in an older British population.
Data from 4428 participants, aged 48-89 years, who attended an eye examination in the third health check of the European Prospective Investigation into Cancer-Norfolk study and had also undergone an ophthalmic examination were assessed. URE was defined as ≥1 line improvement of visual acuity with pinhole-correction in the better eye in participants with LogMar presenting visual acuity (PVA) <0.3 (PVA <6/12). Refractive error was measured using an autorefractor without cycloplegia. Myopia was defined as spherical equivalent ≤-0.5 dioptre, and hypermetropia ≥0.5 dioptre.
Adjusted to the 2010 midyear British population, the prevalence of URE in this Norfolk population was 1.9% (95% CI 0.6% to 3.1%). Lower self-rated distance vision was correlated with higher prevalence of URE (p(trend)<0.001). In a multivariate logistic regression model adjusting for age, gender, retirement status, educational level and social class, independent significant associations with URE were increasing age (p(trend)<0.001) and having hypermetropic or myopic refractive error. Wearing distance spectacles was inversely associated with URE (OR 0.34, 95% CI 0.21 to 0.55, p<0.001). There were 3063 people (69.2%) who wore spectacles/contact lenses for distance vision. Spectacle wear differed according to type of refractive error (p<0.001), and use rose with increasing severity of refractive error (p(trend)<0.001).
Although refractive error is common, the prevalence of URE was found to be low in this population reflecting a low prevalence of PVA<0.3.